The subject of the present invention is an optoelectronic emitter and/or receiver device. It more particularly finds application in the field of high-rate optic connections, notably those respecting usage standards for telecommunications. In the prior art, a device of this type is known, which has a printed circuit on which is positioned an optic emitter-receiver, to emit or receive these optic signals that are exchanged with an optic connector positioned facing this optic emitter-receiver. Such devices dissipate a large amount of energy, and are generally provided with a heatsink or cooler in order to assure their cooling. The interest of the invention is that it presents an optoelectronic device provided with a heatsink, in such a way that the heatsink also serves for a mechanical support for the device.
In the prior art, a parallel optic connection is known from the teaching of document IEEE 078035234 3/99 Electronic Competence and Technologic Conference. This parallel optic connection uses an emitter-receiver and a complementary connector linked to an optical fiber. For this purpose, it has a printed circuit on which is present an emitter-receiver having aligned photodiodes, the printed circuit being designed so that the complementary connector can be mounted on the surface of this printed circuit and presented facing the optic emitter-receiver. For example, the complementary connector has optical-fiber ends connected to this connector with a spacing of its ends equal to the spacing between the photodiodes and the emitter-receiver.
Moreover, in order to assure the correct mounting of the complementary connector on the printed circuit, the printed circuit has two openings and the connector correspondingly has two guiding pins. The position of the optical fiber ends is precisely defined with respect to the guiding pins, and likewise, the position of the photodiodes is precisely defined with respect to the printed circuit openings. Thus, during the mounting of the complementary connector on the surface of the printed circuit, one ends up with a precision optic connection between the optical fibers and the optic emitter-receiver.
This parallel optic connection also has a metal base so as to be able to dissipate the heat emitted by the assembly of electronic components borne by the printed circuit, notably that emitted by the photodiodes. The metal base is a plate applied against one face of the printed circuit, preferentially facing the emitter-receiver. In a preferred example, this metal base also has alignment openings. Thus, the metal base can also receive centering pins from the complementary connector.
In this example, the printed circuit is flexible, and it has several segments permitting a connection with different devices. For example, a first segment is designed to be connected with the complementary connector. In this case, the metal base is applied against only this first segment. On the other hand, a second segment of the printed circuit is provided to be connected, by a bead soldering system, to another device, such as a motherboard, for example. Generally, such a device has a third printed-circuit segment, and said third segment is provided more particularly to receive passive components.
This optoelectronic device of the prior art poses a problem. In fact, such an optoelectronic device releases a great deal of heat. Now the metal base provided to serve as a heatsink is generally of a size that is smaller than the printed circuit. In fact, since the printed circuit is flexible, and the different segments of this circuit are not necessarily aligned, the metal base, which is a rigid plate, cannot follow the different segments of the printed circuit. Therefore, in general, the interest in this metal base is limited to the role of heatsink, in the very restricted zone where the latter is positioned.
Moreover, the flexible printed circuit risks being abraded at the level of the periphery of the metal base. In fact, since this metal base is local, it presents projecting boundary edges to the flexible printed circuit. For example, if the flexible printed circuit is curved in such a way that it is folded on the metal base, then the projecting boundary edges risk cutting the base locally. Moreover, since the metal base is of very fine thickness, this curvature of the flexible printed circuit can lead to the formation of a very crimped bend around this metal base and therefore risks adversely affecting the conductive strips provided in this area on the flexible printed circuit.
The object of the present invention is to solve the problem posed by the optoelectronic device of the prior art. In fact, the optoelectronic emitter and/or receiver device of the invention more particularly provides a device having a printed circuit such that this printed circuit is applied against a heatsink, this heatsink having a form such that it has several distinct faces. The printed circuit has at least one optic receiver and/or emitter, and can receive at least one complementary optic connector, such that the centering pins of this connector can be inserted into the openings of the circuit. In this connection position, the optic contacts of the complementary connector are positioned facing the contacts of the optic emitter-receiver of the circuit.
The printed circuit of the invention is particular since it has a first segment applied against a first face of the heatsink, and a second segment of this same printed circuit applied against a second face of this same heatsink. The particular quality of the invention resides in the fact that the two faces onto which the printed circuit is applied are separate, or, for example, contiguous. The printed circuit also has a flexible segment, such that this flexible segment assures a connection between the first segment and the second segment. The flexible segment permits notably placing the first and the second segments on different planes. Consequently, the heatsink plays a role of physical support for at least these two segments of the printed circuit, and protects them from adverse effects.
The invention therefore concerns an optoelectronic device having a first printed-circuit element, on which is mounted an optic emitter and/or receiver, this first printed-circuit element having at least two openings to receive the centering pins of an optic connector that can be mounted facing the optic emitter and/or receiver, this device also having a heatsink, being characterized in that the first printed-circuit element is applied against a first face of the heatsink, and in that a segment of the flexible printed circuit connects the first printed-circuit element to a second printed-circuit element, this second printed-circuit element being applied against a second face of the heatsink, this second face being separate from the first face.